Floor machine



F. H. CLARKE FLOOR MACHINE July 2, 1935.

2 sheets-sheet i Filed Jan. 3, 1934 WITF July 2, 1935. F. H. CLARKE 2,007,073

FLOOR MACHINE Filed Jan. 5, 1934 2 Sheets-Sheet 2 T'IE" 4 Patented July 2, 1935 vUNITED STATES PATENT OFFICE Claims.

This invention relates to improvements in electric floor machines for grinding, scrubbing and polishing floors.

The invention has for its general object to pro- 5 vide a machine the abrasive or cleaning and polishing elements of which will act with uniform effect upon the floor and will themselves wear evenly throughout their entire surface area.

Other objects and advantages of the invention will be apparent as the speciflcation isl proceeded with and considered in connection with the accompanying drawings, in whichz' Figure l is a perspective view of a preferred embodiment of the invention;

Figure 2 is a side view of the motor and gear housing partly in section;

Figure 3 is a bottom plan view partly broken away and partly in` section showing the driving mechanism;

Figure 4 is a bottom plan of a modification;

Figures 5, 6 and 7 are detail views of the brush members. Thus Figure 5 is a perspective view of the shaft of a brush. Figure 6 is a perspective view of a brush-cover, and Figure 7 is a perspective view of a brush body.

Referring more particularly to the drawings I denotes the machine as a whole comprising a housing or casing 2 supporting the motor 3 and housing the driving mechanism hereinafter described. A pair of rubber tired wheels 4, mounted on an axle 5, in turn secured to the housing 2 by means of a bracket 6, provides convenient means for pushing the machine across the Iiloor. A handle pipe 1, pivotally secured at its lower end to bracket 5, as at 8, is provided at its outer end with hand grips 9. Electrical connection is conveniently made with any suitable source of electric power, such as a house current, by plugging in one end of a line I0 leading along or through the pipe 1 to the motor. The motor at its lower end extends into the casing 2 and is securely fastened to the top thereof by bolts II, the motor and casing being formed with outwardly and inwardly projecting abutting annular flanges I2 and I3 respectively through which the bolts extend for this purpose.

A fixed gear I4, sleeved over the motor shaft I5 is secured to the motor casing by means of bolts I6, and keyed to the lower end of this shaft beneath the gear I4, as at I1, is a disk or fplate I8 on which the brushes and brush driving and idler gears are mounted. A removable collar I9 holds the plate I8 in place and permits of ready removal or replacement. An antifriction bearing 20 interposed between the top of plate I8 and the bottom of fixed gear I4, serves an obvious purpose. Shaft I5 is of course, connected to the motor 3 through reduction gearing, not shown.

'Ihe plate or disk I8, fixed upon and'for rota- 5 tion with the motor drive shaft, rotatably supports a plurality of brushes 2|, 22 and 23, preferably three in number, symmetrically arranged about the motor shaft, and this shaft I 5 is aligned with respect to the axial center of casing or hous- 10 ing 2, motor 3 and plate I8. As the brushes are similar to each other, a, description of the construction and mounting of one will sulce for all. Brush 2|, comprises a body 24 preferably of wood to which bristles 25 are secured in any suitable 15 manner. A stub shaft 26 loosely mounted in a bearing 21 formedin plate I 8 extends at its lower end through an elongated slot 28 formed in a removable cover 29 and thence into an elongated recess 30 formed in the brush body 24 at right 20 angles to but in partial register with the slot 28.

A driving pin 3l engages the side walls of recess 30 and'drives the brush when stub shaft 26 is rotated. Shaft 26 is held in place by a collar 32 and set screw 33. When this set screw is loosened 25 the shaft and its brush can be removed, and if it should be necessary to disconnect the shaft from the brush, this can be readily accomplished by removing cover screws 34 and cover 29.

It is essential that the brush 2l have a'slight 30 rocking movement in order to compensate for rough or uneven places in the floor. Thus .the shaft 26 is formed with a rounded flange 35 or bearing portion which seats in a correspondingly curved cut out bearing portion 36 in the wall of 35' the shaft-opening through cover 29. There is suilicient clearance between the top edge of driving pin 3| andthe bottom of cover 29 to permit of the brush rocking slightly upon the bearing 35-36. A ball bearing 31 takes the stresses be- 40 tween the brush shaft and the'plate.

When the plate I8 is rotated, say in a clockwise direction, the brushes 2I, 22 and 23 will be bodily carried around in the same circular direction about the axis of the shaft I5, which shaft 45 as previously stated is keyed to plate I8. At the same time each brush will be rotated in an cpposite -or anticlockwse direction by its stub shaft, it being understood that each brush is mounted upon and driven by a shaft similar to or identical 50 with shaft 26. Rotation. of the individual shafts 26 is effected by means of three gears 38, 39 and 40 fixed to the respective stub shafts 26 by keys 4I, one for each shaft and gear. 'Ihese fixed gears mesh with three intermediate idler gears 55 42, 43 and 44`mounted upon stud shafts 45, 48 and 41 xed to plate I8. The idler gears just mentioned mesh with and travel around the fixed gear I4 when motor shaft I5 and plate I8 are rotated. Collars 48 and set screws 49 prevent these idler gears from becoming displaced.

The gearing ratio and movement is such that while the brushes as a whole are caused to travel in a. complete circle about the axis of drive shaft I5, each brush will be rotated one complete revolution in a direction opposed to the movement of the brushes as a whole. By virtue of this movement the innermost bristles of each brush travel over the same distance upon each revolution as do the outermost bristles. Consequently the wear on the bristles is substantially uniform. Furthermore the bristles will be progressively subejcted to wear equally on all sides because of the reverse movement and thus are not likely to become bent in one direction only. It will also be noted that the brushes are so arranged as to providefor a free circulation of air, therebetween, thus eliminating objectionable heating of the bristles. y

Instead of providing the brushes with bristles 25, it will be understood that stone or other abrasive disks 50 such as shown in the Figure 4 modification may be employed for certain purposes. It is of course desirable that the working faces of the adhesive disks wear evenly; also that the disks be capable of slight pivotal or rocking movement. As the mounting of the disks 50 will be substantially the same as that of the brushes 2l, these desiderata are obtained. In lieu of the gearing employed for effecting individual rotation of the brushes 2l, the abrasive disks 50 are freely mounted on their shafts 5I. These disks 50 are mounted upon a plate I8' similar to the plate Il, the plate I8' being fixed to and driven from the motor shaft I5, as in the other figures. It has been found that when the members 50 are positively carried around in a circular direction by the motor shaft I5 and the plate I8', these members 58 will be rotated in a contrary direction due to their frictional contact with the floor. The action here is in effect to translate rotary movement into the equivalent of a linear movement, as in the case of the gear driven brushes, and it is also true that for every revolution of the plate I8', each individual disk 50 will be caused to make approximately one complete revolution in a direction opposed to the revolution of plate I8'. It will of course be understood that the gear driven brushes 2l may be provided with abrasive faces instead of bristles and also that the gear drive for the individual brushes 2| may be eliminated.

Having thus described my invention, what I claim is:

1. A fioor machine for grinding, scrubbing and polishing floors, comprising a hollow casing, a motor unit supported on said casing-having its drive shaft extended downwardly into said casing, supporting means rigidly connected to said drive shaft for rotation therewith, a driven shaft rotatably mounted in said supporting means parallel to and in spaced relationship with respect to said shaft, means for rotating said driven shaft with the same revolutions per minute as the said rotatable means in opposite direction with respect thereto and floor working means loosely coupled with said driven shaft to permit tilting of said iloor working means with respect to its shaft.

2. A floor machine for grinding, scrubbing and polishing floors'comprising a hollow casing, a motor supported on said casing having its shaft extended thereinto, means attached to said shaft and rotatable therewith, floor working means rotatably mounted on said first means in spaced relation with respect to said shaft for rotation about an axis parallel to said shaft, and means for rotating said iloor working means the same number of revolutions per minute as said rotatable means in a direction opposite to the rotation of said rotatable'means.

3. A oor machine for grinding, scrubbing and polishing floors comprising a casing, a motor supported on said casing, rotatable supporting means driven by said motor, floor working means rotatably suspended from said rotatable supporting means, in spaced relation with respect to the axis thereof, a gear rigidly mounted on said motor in axial alignment with respect to the axis of said supporting means and gearing on said rotatable means cooperating with said gear and said floor working means in rotating said floor working means in opposite direction with respect to said rotatable supporting means at the rotary speed thereof.

4. In a floor machine for grinding, scrubbing and polishing floors, a casing, a motor supported bysaidcasing,arotatable supporting means driven by said motor, a plurality of axially rotatable oor working means symmetrically suspended from said rotatable supporting means for travel around a common center, a gear non-rotatably secured to said motor and arranged in axial alignment with respect to the axis of said rotatable supporting means, and gearing on said rotatable supporting means engaging said gear and said floor working means for rotating said floor working means in an oppositey direction with respect to said rotatable supporting means at the rotary speed thereof, said floor working means being tiltably suspended from said rotatable means to effect proper surface engagement of all of said floor working means.

5. In a oor machine for grinding, scrubbing and polishing floors, an axially rotatable supporting means, a plurality of axially rotatable shafts mounted on said supporting means in symmetrical arrangement with respect to each other and said supporting means, iioor working means secured to the lower end of said shafts, a gear nonrotatably secured to said machine in axial alignment with respect to said supporting means, gears secured to the other end ofV said shafts for rotating same, and idler gears coupled with said nonrotatable gear and the gears on said shafts for axial rotation of said shafts in a direction opposite to the rotation of said supporting means, said non-rotatable gear and the gears on said shaft having the same pitch diameter to cause rotation of said fioor working means and said rotatable means at the same number of revolutions per minute for insuring equal wear of the working surfaces of said floor working means.

FRANK H. CLARKE. 

